Full or Flat Butt Adjustments

This is the fifth in a series of posts this week on different fitting adjustments you can use for the Clover sewalong, or for nearly any other pair of pants you make. This tutorial is for those with either a full butt (including those with a muscular butt, or just naturally round derriere), or for those with a flat butt.

Fitting notes:

After you’ve made your muslin, please refer to the pants fitting cheatsheet to help you decide which adjustments to try.

Use your muslin to determine how much to adjust the pattern. For example, if you can see that you need an extra inch of width in a certain area, you’ll need to add an inch of width when adjusting your pattern.

Be sure to make a second muslin (and perhaps more) after you’ve adjusted your pattern.

How to use the fitting diagrams:

You will want to trace a copy of your pattern. Not a big deal, since this pattern has only a few pieces, and it will save you from ruining your pattern.

Mark your seamlines on the pattern (5/8″ from the edge). You don’t need to mark it over the whole pattern, but at least mark the seam at the points where the slash lines are. On the diagrams, the seamlines are marked with dashed lines.

The diagrams show where to cut, spread, and overlap your pattern.

You’ll notice little circles in some spots, where the slash lines intersect the seam line. This is called a “pivot point.” Don’t slash the pattern all the way to the edge, but instead slash just to where this circle is. Then carefully snip into the seam allowance, forming a little hinge where the circle is. When you adjust your pattern, you’ll be pivoting at this point rather than from the very edge.

Once you have your pieces adjusted, tape them into place. You can then retrace the pattern piece if you like.

Further help:

I’d love to help you as much as possible, but please realize there are a lot of you and only one of me. Please be sure to help each other out in the Flickr group as much as you can, and check out the fitting section of our Amazon store for further research.

Adjusting for a full butt

1. Draw slash lines, as shown in fig. 1. For this adjustment, you’ll only be working with the back piece.

2. Cut the pattern along these lines. Note the circles, which indicate where you will pivot the pattern. Cut a hinge here in the seam allowance rather than cutting all the way through to the edge (see notes above).

3. Spread the pattern along the yellow and green lines, as shown in fig. 2. Notice that this will increase the width of your dart.

4. Spread the pattern along the blue line, as shown in fig. 3. Overlap at the small pink and purple lines, so that the center back line maintains a smooth angle.

5. Spread the pattern along the red line to increase the width at the inseam, as shown in fig. 4.

6. Tape in place and retrace the pattern piece, smoothing out any lines that need it.

Adjusting for a flat butt

1. Draw slash lines, as shown in fig. 1. For this adjustment, you’ll only be working with the back piece.

2. Cut the pattern along these lines. Note the circles, which indicate where you will pivot the pattern. Cut a hinge here in the seam allowance rather than cutting all the way through to the edge (see notes above).

3. Overlap the pattern along the yellow and green lines, as shown in fig. 2. Notice that this will decrease the width of your dart.

4. Overlap the pattern along the blue line and red line, as shown in fig. 3.

5. Tape in place and retrace the pattern piece, smoothing out any lines that need it.

Comments

I just love your sew alongs, i would love to sew along using your patterns but i live in Dubai. we can’t get mail here to order your patterns. so i would love if you could sell your patterns via email. Some people sell patterns that you can print and paste together via pdf. I would buy them for sure

Alicia – I live in Doha and get the patterns quite easily. I access them from magpie patterns (look them up on line) and get them posted directly to my husband’s work address. Alternatively, set yourself up on Aramex. It works well.

Thank you , I just saw your post . I have yet to try aramex. I am so excited to have her downloadable patterns, it took me a full month just to get her book. Where in Doha are you from, if you come to Dubai look me up for lunch. [email protected]

I understand the principles of ‘adjusting for a full butt’ and how to follow the instructions. Am I missing something, but how do you measure where to put those crucial circles that are the backbone of the job? Im sure where they go must be very important. Thanks and sorry for having a blank spot on this!

Hi Sarai, thanks for the info re the top circle nearest the dart, could you please also tell me how to measure the position of the 2 circles close together on the inside leg seam, that the blue and red lines go out from. Thank you.

Because you will probably need to even out the inner leg seam a little anyway, the exact position doesn’t make a huge difference to the end result.

In other words, wherever you put those circles, there will be a slight bump in the seam. But in step 5, you will be evening out that bump. As long as you place it several inches from the crotch, between crotch and knee, the result will be essentially the same by the time you are done redrawing the curves.

[…] back center seemed way too low. So I made what is basically a big butt adjustment (BBA?) following this diagram from the Colette site. I slashed and spread the back piece as follows (I later filled in the holes with more paper, but I […]

The pants I make are usually a little small in the rear and really too large in the front. I am in need of a slightly larger rear adjustment and a flatter belly adjustment. When looking at the pattern adjustments, it looks to me like doing one would kind of undo the other. Am I missing something?

I’m not sure why that would be the case. All these adjustments are only worked on the back of the pattern, so they have little to no effect on the front (other than the natural changes that come any time you alter a pattern).

[…] to fix that. I adjusted the pattern and lengthened the crotch curve and scooped it out a bit, like this, and like Patti did here. I sewed them up, with the fly and everything, and tried them on […]

[…] A tutorial is currently in the works! In the mean time, have a look Colette’s excellent take on this adjustment. The method I use is a little simpler but doesn’t spread the changes to as many areas in […]